Submitted by leastwood
Staking tokens are used to deposit into the StakingRewards.sol and ConvexStakingWrapper.sol contracts. Once deposited, the user is entitled to Concur rewards in proportion to their staked balance and the underlying pools allocPoint in the MasterChef.sol contract.
The Shelter.sol mechanism allows the owner of the ConvexStakingWrapper.sol to react to emergency events and protect depositors assets. The staking tokens can be withdrawn after the grace period has passed. However, these staking tokens can be deposited into the StakingRewards.sol contract to continue receiving Concur rewards not only for StakingRewards.sol but also for their ConvexStakingWrapper.sol deposited balance which has not been wiped. As a result, users are able to effectively claim double the amount of Concur rewards they should be receiving.
MasterChef.sol
StakingRewards.sol
ConvexStakingWrapper.sol
Ensure that staking tokens cannot be deposited in both the StakingRewards.sol and ConvexStakingWrapper.sol contracts. If this is intended behaviour, it may be worthwhile to ensure that the sheltered users have their deposited balance wiped from the MasterChef.sol contract upon being sheltered.
leekt (Concur) confirmed
Alex the Entreprenerd (judge) decreased severity to Medium and commented:
